Oil-well drill.



3. B. PARKER I R. C. SPURLOCK.y

. OIL WELLVDRILL. 1 APPLICATION FILED nec. 29. ISIS.

Patented Aug. `28, 19W.

WITN ESS ES zml@ ATTORNEY rn raars rami risica,

ROY B. PARKER AND ROBERT C. SPURLOCK, OF MINERAL WELLS, TEXAS.

OIL-WELL DRILL.

Specification of Letters Patent.`

Patented Aug. 2S, i917.

Application led December 29, 1916. Serial No. 139,699.

To all whom t may concern.'

Be it known that we, ROY B. PARKER and ROBERT C. SPURLOGK, citizens of the United States, residing at Mineral Wells, in the county of Palo Pinto and State oi' Texas, have invented new and useful Improvements in Oil-*Well Drills, of which the following is a specification.

This invention relates to improvements in drills and especially with reference to improvements in drills such as are used i'or drilling oil wells, the object of the invention being to provide means to prevent the drill from becoming unscrewed from the drill rod and dropping into the bottom of the well.

' The invention consists in the construction, combination and arrangement oi' devices hereinafter described and claimed.

In the accompanying drawings:

Figure l is an elevation of a drill and the lower portion of a drill rod and showing our improved lock bar which prevents the drill from becoming casually unscrewed from the drill rod.

Fig. 2 is a similar view at right-angles to Fig. l and partly insection.

' Fig. 3 is a detailed perspective view of the locking bar.

The drill l and the drill rod 2, to which the cable is attached are oi' the usual construction, the drill being provided at the upper end of its shank with a screw 3 which engages in a threaded bore in the lower end of the drill rod to connect the drill and the drill rod together. In practice, when the drill is operated by the oil well rig there is a tendency of the drill to become casually unscrewed from the drill rod and to drop to the bottom of the well and this occasions delay and great expense in recovering the drill and before continuing with the drilling of the well.

In accordance with our invention we provide a locking bar 4 which is secured by a screw 5 in a groove 6 in one side of the drill rod and the lower portion of which engages in a groove 7 in one side of the drill shank. This locking bar extends across the joint between the drill rod and the drill and serves to eii'ectually prevent the drill from becoming casually unscrewed from the drill rod, as will be understood. The screw which secures the locking bar to the drill may' be unscrewed when it is desired to loosen the locking bar and permit the latter to be disengaged from the groove in the shank of the drill and thereby permit the drill to be unscrewed from the drill rod.

It will be observed upon reference to the drawings, especially Fig. 3, that the diameter of the opening in the locking bar is much greater than that of the screw, so that the head of the screw fits in the outer side of said opening, and said opening permits angular movement of the locking bar, when the screw has been partially unscrewed, so that the locking bar may be readily disengaged from the groove 7 of the drill shank without having to entirely remove the screw 5. It will also be observed that the groove 7 is closed at a point coincident with the free end of the locking bar and that the locking bar has its free end beveled on the under or inner side to facilitate the detachment of the locking bar from said groove.

Having thus described our what we claim is:

In combination with a drill and drill rod respectively provided with a screw and a threaded bore to detachably couple them together and each also provided with a groove in one side, the opposite ends of said grooves being closed, a locking bar arranged in said grooves and extending across the joint between the drill rod and the drill and having an opening near its inner end and having its outer end beveled on the inner side, and a screw arranged in said opening and detachably securing the locking bar to the drill rod, said opening being of greater diameter than the shank of the screw and the screw having an enlarged head fitting in the outer side of said opening, so that the locking bar is loosely pivotally connected to the screw and may be readily disengaged from the groove of the drill when the screw is partially unscrewed.

In testimonyI whereof we aiiix our signatures.

invention,

ROY B. PARKER. ROBERT C. SPURLOCK.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of'atento,

l Washington, D. C. 

